change default exporter for Node.js to 'otlp/proto'?

[trentm]

By default the NodeSDK will use the http/proto trace exporter. Over time http/proto has become the default OTLP protocol used by most OTel languages. You can see this somewhat from the YAML configuration for the OTel Operator Instrumentation given here: https://github.com/open-telemetry/opentelemetry-operator/blob/main/README.md#opentelemetry-auto-instrumentation-injection

It sets the default exporter to http://otel-collector:4317, which is gRPC, but then has custom env for most languages to change to http://otel-collector:4318, which is an HTTP endpoint (for receiving either http/proto or http/json).

I haven't been involved much with the OTel Operator, but I wonder if it would consider switching the default for nodejs over to http://otel-collector:4318 as well. I realize that would be a breaking change.

The benefit is that "autoinstrumentation.ts" could just use the NodeSDK defaults, and not have to handle selecting a traceExporter at all. The NodeSDK's envvar handling will do the right thing.

Originally posted by @trentm in #3413 (comment)